Questions tagged [lights-out]
A type of puzzle typically involving a grid of lights, in which the challenge is to get them all to the same state (on or off). The trick is that each light also affects a number of its neighbors, with sides and corners affecting fewer.
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Flip counters in a grid so that they alternate in color
Beginner puzzle
This puzzle is intended to be suitable for people who are new to puzzle solving.
Clarification: Both experienced solvers and new solvers are welcome to post solutions to this puzzle.
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Minimum number of flips needed to fully set a binary string
Source: My school teacher, it was just given as a problem statement.
Problem: You are given a binary sequence $S$ of up to $10^6$ bits. You wish to set all the bits in the string to $1$, but the catch ...
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An array of light-bulbs [duplicate]
There is a grid of 2024 by 2024 light-bulbs. Initially, all bulbs are off.
You can switch the state of all 2024 bulbs in a row simultaneously, or all 2024 bulbs in a column simultaneously, and do this ...
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How do I determine whether a 5x5 Lights-Out puzzle is solvable without trying to solve it?
The following two 5x5 Lights-Out puzzles are not solvable. Is there a way to find out why, without trying to solve them?
[1, 0, 0, 1, 0]
[1, 1, 1, 1, 0]
[1, 1, 1, 0, 0]
[0, 0, 1, 0, 0]
[1, ...
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Prime lights out
You start with a 4x4 grid filled with zeroes. If you press a cell then the cell and all its neighboring (horizontally and vertically) cells will have their numbers increased by 1. What is the most ...
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Deemo II Candle Puzzle
I have come across an interesting candle puzzle when playing Deemo II. The puzzle has 8 candles with 2 states: on(○) and off(●).
Initial State
All candles are off:
● ● ● ● ● ● ● ●
Allowed Operation
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What's that puzzle where multiple levers change the locks' states on one door?
I have seen this one a few times in videogames and elsewhere, but I don't remember where.
You have to open one door that has several locks on it. You have a bunch of levers that when moved change the ...
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Name and solution of puzzle to rotate all arrows to same direction
In this puzzle, when you click an arrow, all arrows immediately next to it (diagonally included), as well as the arrow you clicked itself rotate 90 degrees. The goal is to get all the of arrows to ...
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How to get the least number of flips to a plastic chips to get a certain figure?
The puzzle is as follows:
(Transcription with grammar errors fixed)
A game consists of the following:
The challenge is to flip the chips in such a way so that they are as in state 2. You start in ...
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Maximising the number of lit lightbulbs through row-column toggling
You have an $n\times n$ grid, with each cell containing a lightbulb. On a move, you may select a lightbulb, and toggle the state of that lightbulb, and all other lightbulbs sharing a row or column.
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The combinational switching lights
You have probably encountered the mini puzzle in various games where you have a set of switches and a set of lights (or other triggers), such that each switch "flips" the states of one or ...
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Flipping coins in a circle
We have a set of N coins that are all placed in a circle. They all have "Tails" as their face up side. The coins are all distinct and have numbers (1,2,3...N) written on them.
In each move, ...
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Highest n where an equal number in all cells is (im)possible
Inspired by Board with all 2020s :
Zeroes are written in all cells of a n×n board. We can take an arbitrary cell and increase by 1 the number in this cell and all cells having a common side with it.
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Different numbers in all cells of a 4x4 board
This is a harder version of this puzzle: Different numbers in all cells of a 3x3 board
Zeroes are written in all cells of a 4×4 board. Pressing a cell increases by 1 the number in this cell and all ...
- 36.3k
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Different numbers in all cells of a 3x3 board
This puzzle is inspired by this one: Board with all 2020s
Zeroes are written in all cells of a 3×3 board. Pressing a cell increases by 1 the number in this cell and all cells having a common side with ...
- 36.3k